On Monday 25 June 2007, Timothy Normand Miller wrote: > It has become apparent that although the video controller design makes > all sorts of things possible, it also makes some things rather > inconvenient. > > Example: double buffering > > For this, you have to update the viewport pointer every frame (or > every time you want to switch views). The problem is that the pointer > is not stored in a fixed location in the video program, and it's split > across two instructions. > perhaps we could have the vc compiler function (progressive, interlaced, > etc.) fill out a struct with some key information, such as the addresses of > the ADDR and INC instructions that contain the pointer.
Is this worth the hassle compared to just rerunning the VC program generator? If regenerating the whole program is undesirable, I suggest generating two functions: The existing function that generates a whole program, and a second function that just modifies the frame base of an existing program. Maybe have it return the region of the program that has been modified. That way all knowledge of the VC instruction set is confined to one place. > Example: knowing when you're in vertical blank > > Windows drivers want to know when you're in vertical blank and when > you're not. Could we use the cursor position for this? Or expose the VSYNC signal? Paul _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
